Share Email Print
cover

Proceedings Paper

Spectral representation: a core aspect of modelling the response characteristics of time-domain EMI mine detectors
Author(s): G. F West; R. C. Bailey
Format Member Price Non-Member Price
PDF $14.40 $18.00

Paper Abstract

Most modern EMI mine detectors can detect the very small conductive and/or ferromagnetic parts of typical mines with relative ease. However, they also respond significantly to certain soils that contain lossy ferromagnetic minerals. In some special environments such as ocean beaches, conductivity of the host soil may also cause a response. Characterizing and modelling both the various target response mechanisms and the EMI detectors quantitatively would be relatively straightforward if it were not for the fact that most modern EMI detectors operate in time domain and use different current waveforms and time gates to observe response. Furthermore, much of the information about targets and interferences and even instrumental spectral limitations is observational rather than analytical data. In this paper, we put forward a spectral representation method that can be incorporated into both EMI data gathering and instrument modelling and which facilitates efficient quantitative simulation of arbitrary time- domain detection systems. The methodology and examples of its use are presented. Pure induction response from the ground is modelled with a sum-over-N-elements transfer function in which the kernel elements are single pole, pure damping responses which are log-spaced over the spectral range of interest. Instrument transfer functions can be described with a standard sparse pole and zero representation (located anywhere in the damped frequency half plane), if required. Model fitting techniques employing generalized inversion controls are used to go back and forth between frequency and time domain and the set of model parameters.

Paper Details

Date Published: 16 May 2006
PDF: 12 pages
Proc. SPIE 6217, Detection and Remediation Technologies for Mines and Minelike Targets XI, 621702 (16 May 2006); doi: 10.1117/12.665898
Show Author Affiliations
G. F West, Univ. of Toronto (Canada)
R. C. Bailey, Univ. of Toronto (Canada)


Published in SPIE Proceedings Vol. 6217:
Detection and Remediation Technologies for Mines and Minelike Targets XI
J. Thomas Broach; Russell S. Harmon; John H. Holloway, Editor(s)

© SPIE. Terms of Use
Back to Top